Rachel Reeves is planning a round of deep public spending cuts as she struggles to balance the books amid the mounting global turmoil.

The chancellor will set out her plans to the Office for Budget Responsibility (OBR) later today after the amount of spare money she expected to have – her so-called “fiscal headroom” – was wiped out.

It means she will unveil plans to reduce the UK’s soaring welfare bill, as well as cuts to other unprotected government departments, when she updates the Commons on her updated budget plans on March 26.

A government source told HuffPost UK: “Clearly the world has changed a lot since the autumn Budget. People are watching that change happen before their eyes. 

“The UK is in a strong position to weather that change. But, a changing world means we must go further and faster in pushing through the change we promised at the election.

“We don’t need the OBR to tell us that we need to fix welfare to get people back to work. We don’t need the OBR to tell us we need to make the NHS more productive. And we don’t need the OBR to tell us that the taxpayer should be getting more value for money.

“Headroom or no headroom, the chancellor is determined to push through the change we need to make Britain more secure and prosperous, with the whole government making that argument in the coming weeks.”